Those who have tried the extreme eating plan give mixed reviews: some swear by the starve-fest, while others are more skeptical about about its benefits.

Katy Latta, an executive in the U.K, has been on the fast diet for two weeks. She's lost 4 pounds, but it's hardly been smooth sailing.

"When I’m fasting all I can think of is food and when I’m feasting all I can think of is fasting!" Latta said via email.

Birthday cake always seems to be calling her name at the office, and going out to eat with co-workers, friends, or family is no longer enjoyable.

"Food is at the heart of most social occasions, and counting calories sucks the joy out of it for you and the people your with," she said.

There are also some unpleasant side-effects of limiting food intake to less than 500 calories a day during fasting periods. Latta says she's been extremely irritable, has experienced nausea, and has difficulty sleeping while on the diet.

On the hand, many people embrace the diet because they can eat the foods that they typically enjoy for most of the week.

There's also a sense of achievement once you lose the weight. "It does feel good to prove to yourself you have that kind of self-control," Latta adds.

The infographic below created by supplement retailer Holland and Barrett lays out the pros and cons of the 5:2 diet. Is it worth it? You decide after reading the good and the bad: